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How to program Taranis with homemade "tank"

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How to program Taranis with homemade "tank"

Old 02-15-2021, 02:13 PM
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mantafloppy
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Default How to program Taranis with homemade "tank"

Hi, i've search around, and i cant seem to find how to do something that i tought would be simple.

I've made a tank, simple, 2 track, with each a drone motor with a ESC each, both plug strait to the receiver.

Both stick on the Taranis X7 are set to self center, and i want each track to be control by one stick.

So i need to set the "0"/neutral to the center of the stick and 100% at the top. (Or you can see it as both stick are throttle, but need to be neutral at the center) .

I'm able to get it to work with a Elevon mix, but thats not ideal.

Seem i will need special ESC to get reverse, so that gonna be for later, but if you know how to set that up at the same time, the knowledge is welcome.

Thx for any help.

P.S. The tank i'm refering to, i'm not the creator : thingiverse thing:4234076
Old 02-15-2021, 02:38 PM
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RC_BobM
 
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floppymanta,
I use Sabertooth ESC and they have a DIP switch setting which allows you to easily switch from 2 stick control to controlling 2 motors with one single stick. I don't know if this is possible with the brushless motors (you say drone motors) and the ESC's you are using. Also don't know if your ESC allow for motor reversing or not (not generally good on an brushless airplane or drone motor) without changing the connection polarity of the motor. The Sabertooth allows for motor reversing for brushed motors - from radio as well.

It seems like it should be possible with some kind of 2 channel mixing and a Y adapter cable to the Throttle channel (like twin engine airplane)? But cannot guarantee that setup would work for moving vehicle in reverse.

You want a single robot or surface vehicle ESC that specifically allows for controlling 2 motor, allows for motor reversing and one stick control.

Sorry can't offer much more than that....
B
Old 02-15-2021, 03:08 PM
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tankme
 
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Simple and cheap. Need a V-tail mixer to plug both ESCs into. V-tail mixer is plugged into the receiver that corresponds to the two channels on the single stick: https://hobbyking.com/en_us/turnigy-...tra-small.html
For brushed motors cheap ESC that reverses: https://hobbyking.com/en_us/hobbykin...en_us_products
For brushless motors cheap ESC with reverse: https://hobbyking.com/en_us/hobbykin...en_us_products

Those are just suggestions as I don't know the size or type of motor you are using. I also don't know your battery voltage so YOU need to figure out if those ESCs are appropriate for your application (IE: right voltage range for your batteries and amp range for your motors).
Old 02-15-2021, 03:27 PM
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mantafloppy
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Thx, so seem I'm missing some hardware for the stick controll.

I already have some BlHeli Esc that can be program for reverse, but I don't have the programmer... It's in the mail.

I think I have all the info I need, thx again all.
Old 02-15-2021, 10:35 PM
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Rad_Schuhart
 
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Originally Posted by mantafloppy View Post
Hi, i've search around, and i cant seem to find how to do something that i tought would be simple.

I've made a tank, simple, 2 track, with each a drone motor with a ESC each, both plug strait to the receiver.

Both stick on the Taranis X7 are set to self center, and i want each track to be control by one stick.

So i need to set the "0"/neutral to the center of the stick and 100% at the top. (Or you can see it as both stick are throttle, but need to be neutral at the center) .

I'm able to get it to work with a Elevon mix, but thats not ideal.

Seem i will need special ESC to get reverse, so that gonna be for later, but if you know how to set that up at the same time, the knowledge is welcome.

Thx for any help.

P.S. The tank i'm refering to, i'm not the creator : thingiverse thing:4234076
Looks like you are using the wrong motors and ESCs. most drone and aircraft equipment has only one way throttle, so top down is off, middle is 50% gas and up is 100% throttle. You need other equipment which lets you have reverse. There are cheap 2ish eur free shipping ESCs and tiny, that will be powerfull enough for your tank.

About the hardware our colleagues told you you need, well, forget it. Many times I see people here recommending loads of strange hardware when all of that can be done just with the programmable radio you have. If you had crappy radios, then yes, but it is not the case.
You only need to asign some offset to your two sticks, so center will be 0 throttle and top up 100% throttle. No need to connect anything extra.
Old 02-16-2021, 03:56 AM
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mantafloppy
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Reverse is not actually important at this point.

I'll try to apply some offset then, see what I get.
Old 02-16-2021, 10:22 AM
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mantafloppy
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Thx Rad Schuhart , just tried -100 offset on ch 1 and ch 3, and everything work as i wanted.

I know brusheless motor are not ideal and i dont have the right ESC/harware for reverse, but that good for now. I just copied someone else project and was'nt ready to make those change yet .
Old 02-16-2021, 11:09 AM
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Imex-Erik
 
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Originally Posted by mantafloppy View Post
Thx, so seem I'm missing some hardware for the stick controll.

I already have some BlHeli Esc that can be program for reverse, but I don't have the programmer... It's in the mail.

I think I have all the info I need, thx again all.
As someone with a bit of MR experience here I can help a bit. BLHeli does support 3D, so you don't need new ESCs. However BLHeli is a bit old in the tooth, so when/if you reorder try to get a BL32 version as it has a lot of features for the same price. A nice 30A single shouldn't cost more than $10-15ish. Now to program you have a few options but the easiest is to use a cheap flight controller and go through something like Speedybee on Android. If not you can program your ESCs through a PC via passthrough to which there is a lot of info on that online. A cheap flight controller will also help with mixing, you assign the tank as a wing and the up/down of the ailerons is actually the same commands as tank controls. The flight controller could also handle extra assignments, fail-safes, FPV control, serial outputs, etc. I use FCs on almost all my cars and even rovers these days.
Your bigger issue is going to be starting torque. Unless that is a sensored brushless motor (which BLHeli doesn't support) the motor is going to have a lot of cogging until it starts to move. This will cause desyncs with BLHeli as they do not like cogging. You might have to actually bump start it with your foot if your KV is too high. I did some testing a few years ago with brushless stuff and unless you completely overpower the drive system brushless just isn't worth the extra money I found. That doesn't mean it wasn't super fun though! I would suggest reading into the BLHeli settings such as demag compensation, timing, min throttle (gonna have to set the ESC as a 3d quad), and possibly timing too. Also check out the arm procedure for a 3d quad too, it will be different than a normal quad/car.

Hope this helps!
Old 02-16-2021, 11:42 AM
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Originally Posted by mantafloppy View Post
Thx Rad Schuhart , just tried -100 offset on ch 1 and ch 3, and everything work as i wanted.

I know brusheless motor are not ideal and i dont have the right ESC/harware for reverse, but that good for now. I just copied someone else project and was'nt ready to make those change yet .
Yeeeeeeeeeeeeeeehaaaaa! Glad it worked!
Old 02-16-2021, 12:25 PM
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mantafloppy
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@ Imex-Erik, thx for all the info. I already have the ESC, there call Favorite Opto Little Bee 30A, and i have a Usb programmer in the mail.

The one install right now is what was relativle cheap, Amazon prime shipping, with a signal cable, that i could found, so they are like 80 amp :P I didnt want to wait an other 50 day shipping from Banggood.

You seem to know your brushless, cause it need to be kick sometime to start up, but it is gear down a lot, like silly, i think its 51 to 1? I run 5010 360KV on 6S.

i cant post link or picture cause i'm new, but if wanna see :
imgur g0OMCpM
imgur ifA5EcG
Old 02-19-2021, 02:55 PM
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Originally Posted by mantafloppy View Post
@ Imex-Erik, thx for all the info. I already have the ESC, there call Favorite Opto Little Bee 30A, and i have a Usb programmer in the mail.

The one install right now is what was relativle cheap, Amazon prime shipping, with a signal cable, that i could found, so they are like 80 amp :P I didnt want to wait an other 50 day shipping from Banggood.

You seem to know your brushless, cause it need to be kick sometime to start up, but it is gear down a lot, like silly, i think its 51 to 1? I run 5010 360KV on 6S.

i cant post link or picture cause i'm new, but if wanna see :
imgur g0OMCpM
imgur ifA5EcG
The little bees had a TON of issues, mainly motor noise when it came to tuning. I used to run the LBs until the Super Bees came out that fixed a lot of the noise issues they had in the first batch. They did have a tendency to burst into flames so just be careful there. These here: https://pyrodrone.com/collections/in...for-fpv-racing have some REALLY good specs and I personally put 40A+ for 3-5m, 10-20+ times a day for well over 6 months with those equipped and they were flawless. They are also 32bit and BLHeli. You can get flight controllers here: https://pyrodrone.com/collections/fl...rice-ascendingwhich also not only double as a programmer but a controller as well. The boards are all open source and even open hardware. You can run betaflight or iNav on it with iNav focusing on tanks, rovers, planes, etc that are autonomous. If I get some spare time this year sometime I'll sit down and do a full build for everyone so they can see how it works. The tanks can be controlled quite easily with flight controllers or you can even just use them as a passthrough or to use other serial devices like GPS, bluetooth, bi-directional telemetry, or more.
If you can try not to buy anything from Amazon. The cut they take from your local shop (no matter if it is hobbies or not) is pretty bad and hurting a lot of local businesses, not just hobbies. If you can, try to buy from a brick and mortar store first or at least someone that is promoting or supporting the hobby. Pyro, GetFPV, and RDQ are the biggest contributors to the FPV industry and have done a lot fighting for our rights in the air as well as for all hobbies. Any purchase from those three supports the hobby a bit extra plus they also give back to the local race groups and sponsor events and such too. I would be more than happy to assist with what you need here albeit a bit slow as I'm not on here daily.
Old 02-21-2021, 11:43 AM
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mantafloppy
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Thx again, ill go with new ESC and a flight controller then.

I'm looking at the schematic and now i'm wondering about the Receiver. If i go with a Mamba F405, do i need a special receiver, or can i use what i already have : RadioMaster R86.

If i can use the old one, could you point out a guide or tell me wich cable would go where on the FC?
Old 02-22-2021, 08:07 AM
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As long as that rx is compatible with your transmitter and/or module then yes you can use the FC with as far as I'm aware almost any hobby communication protocol from PWM to CRSF and more. As for programming with the OpenTX system I would check out OpenTX University's site, they have a ton there.

Some resources for you:For the connection that really matters on what protocol you are going to use. PWM really isn't needed and is a PITA to deal with as well as a huge amount of latency versus even just PPM. sBus is a world of difference from PPM and we have since moved way past sBus to better and faster protocols. Use the best your receiver offers, most likely sBus or PPM. PPM can handle 8-12ish channels depending on brand and sBus can do 16 per signal wire. No need to use more than one signal wire. If you use PPM it will go to any RX pin and if you use sBus it will go to the sBus port as that UART is inverted for the F4 cpu.

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